1. Field of the Invention
The present invention relates to hand tools, and particularly to a modular wrench with an extendible handle to fit into tight places and to provide increased torque.
2. Description of the Related Art
One of the most commonly used tools in the mechanic's toolbox is the wrench. Wrenches are available in a variety of styles and sizes, the most common being the open end wrench, the box end wrench, and the combination wrench. In many cases a socket wrench can be used to do the same job faster. Nevertheless, the standard flat wrench is still the tool of choice, particularly with the crowded nature of the engine compartment in today's automobile. Quite often the only tool that will fit into tight areas is the standard flat wrench.
However, tools are expensive, and a common problem is that wrenches are needed in a variety of lengths. In restricted spaces, a short, stubby wrench is required, while for other applications a wrench with an elongated shank or handle is required in order to reach the fastener. The mechanic often finds that Murphy's Law applies, and that he doesn't have a wrench of the proper size with a shank or handle long enough to reach the fastener he's working on. While wrenches with extra long shanks may be available through specialty catalogs, they are usually not commonly available at the local hardware or department store. Furthermore, in order to be prepared for any fastener that may be encountered, a multitude of wrenches with shanks of various lengths would have to be purchased.
Consequently, there is a need for a wrench with an extendible shank. Although extendible handles for brooms, mops, and other such pole tools are common, and several devices are available to extend the length of a socket wrench ratchet handle, few efforts have been directed towards extending the reach of a conventional flat wrench.
U.S. Pat. No. 1,511,738, issued Oct. 14, 1924 to F. W. Lownsbery, describes a flat extension handle to extend the reach of a wrench. The wrench is placed against the side of the extension handle and retained by clips extending from opposite sides of the extension handle. A spring-biased stud extends from one edge of the handle to prevent the wrench from rotating free of the clips.
The Snap-On Tools catalog of January 1995 shows heavy-duty/striking wrenches at page 127. The wrenches are available in either open end or box end style, and have a cylindrical shank with a wrench head at one end of the shank. A cylindrical, tubular extension handle can be placed on one end of the shank, and is secured thereto by a locking button. The tubular extension handles are available in lengths between 13½″ and thirty-six inches.
Extendible handles for socket wrenches are shown in U.S. Pat. No. 2,964,981, issued Dec. 20, 1960 to O. T. Blunt (foot-operated torque wrench with telescoping arm clamped by thumbscrew); U.S. Pat. No. 4,586,406, issued May 6, 1986 to W. H. Howard (torque wrench with telescoping handle sections secured by detent pins and released by slidable sleeve); and U.S. Pat. No. 6,378,400, issued Apr. 30, 2002 (socket wrench with multiple, inextensible handles and a socket head that can snap onto each handle in turn).
Extendible handles for brooms, mops, and other appliances with pole handles are disclosed in U.S. Patent Publication No. 2003/0163897, published Sep. 4, 2003 (segmented handle with male and female ends that friction fit with a ring over the joint); U.S. Patent Publication No. 2003/0204926, published Nov. 6, 2003 (handle with two segments joined by a link using threaded connection); U.S. Patent Publication No. 2003/0233718, published Dec. 25, 2003 (handle with segments having “ratchets” and “bosses” that twist together to permanently lock segments together); U.S. Patent Publication No. 2003/0235463, published Dec. 25, 2003 (handle with two segments having tabs and recesses that permanently lock segments together when pushed axially); and U.S. Pat. No. 2,697,642, issued Dec. 21, 1954 to J. Rudy (magnetic connector for attaching a broom handle to a broom head, mop head, or the like).
U.S. Pat. No. 4,300,607, issued Nov. 17, 1981 to Mellinger, teaches a variable length tool handle for a screwdriver or the like having upper and lower portions locked together by a detent mechanism. U.S. Pat. No. 5,873,148, issued Feb. 23, 1999 to R. L. Arnold, describes a contoured, segmented grip for a screwdriver or the like having multiple segments axially slidable on a sleeve.
None of the above inventions and patents, taken either singly or in combination, is seen to describe the instant invention as claimed. Thus a modular wrench with an extendible shank solving the aforementioned problems is desired.